// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef MEDIA_AUDIO_ANDROID_AUDIO_RECORD_INPUT_H_
#define MEDIA_AUDIO_ANDROID_AUDIO_RECORD_INPUT_H_

#include <stdint.h>

#include <memory>

#include "base/android/jni_android.h"
#include "base/macros.h"
#include "base/threading/thread_checker.h"
#include "media/audio/audio_io.h"
#include "media/base/audio_parameters.h"

namespace media {

class AudioBus;
class AudioManagerAndroid;

// Implements PCM audio input support for Android using the Java AudioRecord
// interface. Most of the work is done by its Java counterpart in
// AudioRecordInput.java. This class is created and lives on the Audio Manager
// thread but recorded audio buffers are delivered on a thread managed by
// the Java class.
class MEDIA_EXPORT AudioRecordInputStream : public AudioInputStream {
public:
    AudioRecordInputStream(AudioManagerAndroid* manager,
        const AudioParameters& params);

    ~AudioRecordInputStream() override;

    // Implementation of AudioInputStream.
    bool Open() override;
    void Start(AudioInputCallback* callback) override;
    void Stop() override;
    void Close() override;
    double GetMaxVolume() override;
    void SetVolume(double volume) override;
    double GetVolume() override;
    bool SetAutomaticGainControl(bool enabled) override;
    bool GetAutomaticGainControl() override;
    bool IsMuted() override;

    static bool RegisterAudioRecordInput(JNIEnv* env);

    // Called from Java when data is available.
    void OnData(JNIEnv* env,
        const base::android::JavaParamRef<jobject>& obj,
        jint size,
        jint hardware_delay_bytes);

    // Called from Java so that we can cache the address of the Java-managed
    // |byte_buffer| in |direct_buffer_address_|.
    void CacheDirectBufferAddress(
        JNIEnv* env,
        const base::android::JavaParamRef<jobject>& obj,
        const base::android::JavaParamRef<jobject>& byte_buffer);

private:
    base::ThreadChecker thread_checker_;
    AudioManagerAndroid* audio_manager_;

    // Java AudioRecordInput instance.
    base::android::ScopedJavaGlobalRef<jobject> j_audio_record_;

    // This is the only member accessed by both the Audio Manager and Java
    // threads. Explanations for why we do not require explicit synchronization
    // are given in the implementation.
    AudioInputCallback* callback_;

    // Owned by j_audio_record_.
    uint8_t* direct_buffer_address_;

    std::unique_ptr<media::AudioBus> audio_bus_;
    int bytes_per_sample_;

    DISALLOW_COPY_AND_ASSIGN(AudioRecordInputStream);
};

} // namespace media

#endif // MEDIA_AUDIO_ANDROID_AUDIO_RECORD_INPUT_H_
